


A Story For Sans

by agerefandom (tazia101)



Category: Undertale (Video Game)
Genre: Age Regression/De-Aging, Emotional Hurt/Comfort, Gen, Non-Sexual Age Play, Papyrus takes care of sans, Unhealthy Eating Mentioned, agere, regressor!sans, we need to get some better regression tags
Language: English
Status: Completed
Published: 2020-05-27
Updated: 2020-05-27
Packaged: 2021-03-02 19:35:54
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,213
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24412165
Author URL: https://archiveofourown.org/users/tazia101/pseuds/agerefandom
Summary: Sans isn't taking care of himself and Papyrus decides it might be time for a break, not knowing that Sans is on the verge of regressing from exhaustion. (prompt received on tumblr)(Featuring regressor!Sans and a confused but enthusiastically loving Papyrus)
Relationships: Papyrus & Sans (Undertale)
Comments: 2
Kudos: 84





	A Story For Sans

**Author's Note:**

> Originally posted on my tumblr, @agerefandom, where I take requests from sfw blogs for age regression fanfiction! 
> 
> I tag my AO3 stories with non-sexual kink tags because there's no good system for non-kink regression at the moment, though I'm hoping the 'agere' tag will catch on. Hope you enjoy!

Sans disappeared sometimes.

This was a fact of life that Papyrus had come to accept. Sans disappeared into the workshop under their house, into the forest, into the Hotlands. Sometimes Papyrus would find him in the morning, asleep half-way up the stairs. Other times, Alphys would find him sleeping in her lab and call Papyrus to come pick him up. Some mornings, Grillby would walk Sans home, three polite knocks announcing their arrival and scorching the wooden door.

Papyrus worried.

This, too, was a fact of life. Papyrus worried about his brother’s HP; Sans had never let him see the exact number, but Papyrus knew that it was low. Papyrus worried about the way his brother slept away every hour that he could, his eyes half-focused and hazy as he stumbled from nap to nap. And no matter how many times Sans vanished and reappeared safe and sound, Papyrus worried every single second that he was gone.

Two nights ago, Sans had disappeared out the door after dinner, and he hadn’t come back. Papyrus had kept an eye on his sentry stations (or hot dog stands) and did his best to remind himself that Sans always, _always_ came back safe.

By the third morning, Papyrus couldn’t focus on his patrols or his exercises or his puzzles, the worry a constant distraction. He couldn’t wait any longer; he needed to find his brother.

His first stop was Grillby’s. Grillby said that he hadn’t seen Sans in a few days, and Papyrus’s anxiety twisted tighter around his ribs. When Sans wasn’t eating at Grillby’s, he usually wasn’t eating at all.

Papyrus’s second stop was Sans’s bedroom, holding his scarf over his lack of a nose. It was as dirty as ever, the bed too messy to judge how recently it had been used, the trash tornado still spinning away. Nothing unusual, and no way to know if Sans had been here.

Papyrus closed the door with a sigh.

There was one last place to check before he had to venture outside of Snoden, and Sans wouldn’t be happy about it. He hated it when Papyrus went into his workshop, but three days was enough time that Papyrus was determined to do whatever it took.

One carefully shaped bone attack let Papyrus pick the lock on the workshop door, and soon he was stepping onto the rotting wooden steps that led to their basement.

He could immediately see that the lights were on down there, and he made his way down quickly, caught between relief and anger as he caught sight of his brother’s familiar sweater flung over the back of a chair.

“go away, papyrus.” Sans’s voice was rougher than usual, and Papyrus took a moment to look around at the space. The couch had been slept on, and there were empty bags of chips scattered across the floor. Sans was crouched on the other side of the room, dressed in a dirty white shirt. The mysterious machine was in front of him, a panel open to show the gears and circuitry inside. Sans wasn’t looking at Papyrus, running his fingerbones over the parts of the machine.

“SANS! IT HAS BEEN THREE DAYS SINCE YOU’VE BEEN AT YOUR SENTRY POSTS!”

“yeah, i know… i’m busy, pap.” Sans’s voice was flat, his face still turned away from Papyrus.

“BROTHER…” Papyrus searched for something to say. “THIS ISN’T HEALTHY! YOU SHOULD COME UP FOR DINNER.”

“i’ll come up later. soon.” Papyrus wished that Sans would look at him. The worry was back, familiar and uncomfortable.

“WHEN THE GREAT PAPYUS EXTENDS A DINNER INVITATION, IT DOES NOT GET TURNED DOWN!” Papyrus tried. Referring to himself in third-person usually made the corners of Sans’s eye sockets crinkle. But today, he just kept facing the machine in the corner.

“sorry, bro. another time.”

It was the lack of puns that finally pushed Papyrus over the edge. His use of ‘turned down’ should have gotten a bad joke, at least, and there were the million things that Sans could have said about his work ethic, but instead it was just these monotone statements. Something was wrong. Papyrus knew from experience that Sans didn’t like talking about the things that bothered him, so trying to make him talk would only make things he was worse. But he was The Great Papyrus! He must, _must_ be able to fix this!

It was with that final thought that Papyrus strode forwards and wrapped his arms around his brother from the back. He gave Sans a moment to register what was about to happen: enough time for Sans to pull his hands out of the machine gears, but not enough time for him to slip out of Papyrus’s grip.

And then Papyrus hoisted him up into the air.

Sans was easy to pick up; for all his width, he was still made of bones and magic, just like Papyrus. Papyrus took a moment to adjust his grip, flipping Sans around so that he was settled on Papyrus’s hip, and then started carrying his big brother towards the stairs.

“wh- hey! papyrus, put me down!” Sans’s objections went unheeded as Papyrus climbed the stairs to the outside, his only response to wrap his arms tighter around Sans as he struggled.

“YOU CAN GO BACK TO YOUR WORK TOMORROW,” Papyrus informed him, marching to the front of the house and trying to get the door open before anyone could walk by and see the odd scene. It took a few moments for him to manage the still-wriggling Sans and the doorknob, but soon enough he was stepping into the house. “FOR NOW, I AM GOING TO MAKE YOU A MEAL AND YOU ARE GOING TO EAT IT!”

“pap- i don’t want -” Sans was still pushing against Papyrus’s shoulders, but his efforts were weaker than Papyrus had expected. Sans could have avoided Papyrus from the beginning, if he’d been anything close to his normal speed. The fact that he couldn’t get free of Papyrus’s grip made Papyrus even more sure that he’d done the right thing bringing Sans up.

“papyrus, put me down!” Even if Sans himself didn’t agree.

“SHUSH.” Papyrus ran his gloved fingers lightly over the back of Sans’s skull, a calming gesture that he remembered Sans using on him when he’d been younger. “TAKE A BREAK, SANS. YOU NEED IT.”

Papyrus didn’t know if it was the words or the slow petting motion, but Sans suddenly slumped against his shoulder, his hands holding onto Papyrus’s scarf instead of trying to push him away. Papyrus felt his arms starting to get tired; made of bones or not, Sans was still a full-grown monster and Papyrus had carried him up a flight of stairs.

Papyrus made his way over to the couch and sat down. He tried to let Sans go, but Sans continued to hang onto Papyrus’s scarf, hiding his face against his chest-plate. Papyrus gave him a second to move away, and when Sans didn’t, he carefully gathered his big brother onto his lap and wrapped his arms around him.

Cuddling wasn’t rare for the two brothers, curled up on the couch watching TV after a long day at work (for Papyrus) or a long day of naps (for Sans). This felt different, though, like something precious that Papyrus had to be careful with.

He slipped off his gloves and resumed the petting of Sans’s skull, his bare phalanges rasping against the curves and raised lines of bone. Sans relaxed even more against him, a low sound like a hum coming out of his chest, vibrating against Papyrus’s ribs. Sans’s head turned into the touch, enough that Papyrus could see his face.

Sans was dirty with sweat and dust from the machinery. The shadows beneath his eyes were even deeper than they normally were, almost as though they had been carved into his skull. Despite that, his eyes were now closed and his face was peaceful.

“I MISSED YOU,” Papyrus found himself admitting, running his fingers over Sans’s zygomatic bones and gently over the nasal cavity.

“missed you too.” Sans’s voice was sleepy, distant and low.

“I WISH YOU HAD TOLD ME YOU WOULD BE AWAY SO LONG. I COULD HAVE BROUGHT YOU FOOD.”

“i like food,” Sans told him, rubbing one cheek on Papyrus’s chest-piece.

“AND ESPECIALLY WHEN IT IS MADE BY THE GREAT PAPYRUS!” Papyrus said, pressing his free hand to his chest proudly, unwilling to take his hand off of Sans when he was so obviously enjoying the petting.

Sans nodded against Papyrus. Papyrus could tell that he was halfway to falling asleep, so he decided that food could wait until after a nap.

“DO YOU WANT TO SLEEP ON THE COUCH, OR IN YOUR BED?”

“race car,” he heard Sans reply, muffled against Papyrus’s chest.

“YOU WANT TO SLEEP IN MY BED? IT IS THE COOLEST BED!”

He felt Sans nod. “story,” Sans said.

“YOU WANT… ME TO READ YOU A BEDTIME STORY?” Papyrus’s bed was where they curled up every night so that Sans could read Papyrus his favourite book before bed, Peek-A-Boo with Fluffy Bunny. Papyrus had never, ever read Sans a bedtime story. But Sans seemed so sleepily certain that this was the way things should be, and he was finally relaxed and agreeable to being dragged away from his work…. And in the end, there wasn’t a single thing that Papyrus wasn’t willing to do for his brother.

“not th’ bunny one,” Sans muttered.

“YOU DON’T WANT TO HEAR PEEK-A-BOO WITH FLUFFY BUNNY?” Papyrus asked, somewhat affronted.

“s’your book. i want a different book.”

“WELL, ALRIGHT! I’LL FIND YOU A BOOK, BUT LET’S GET UP TO BED FIRST. CAN YOU WALK?” Papyrus felt Sans shake his head. “ALRIGHT, LAZYBONES. UP WE GO!”

He scooped Sans up in his arms with a flourish, and Sans actually _laughed_ , not his usual low chuckle but a higher giggle that Papyrus hadn’t heard from him in years and years and years. It made Papyrus hug his brother tight for a long moment, trying not to think about how much they had been through together.

When he could loosen his grip, Papyrus got up from the couch and settled Sans back on his hip, a motion becoming more familiar. The stairs were easy enough, but he paused at the top of the stairs.

“SANS, YOU’RE VERY DIRTY! PERHAPS YOU SHOULD TAKE A BATH BEFORE GOING TO BED!” Sans shook his head vigorously.

“bath later,” he told Papyrus, his voice certain. “bedtime now.”

Papyrus obediently headed for the bedroom, resigning himself to washing his sheets when Sans woke up. It was hard to get the door open with his brother in his arms, but much easier now that said brother wasn’t squirming with all of his strength.

He deposited Sans on the bed, disentangling his hands from his scarf gently. “TAKE OFF YOUR FILTHY CLOTHES AND I WILL FIND YOU NEW ONES,” Papyrus instructed, and stayed around long enough to see Sans start to slip off his shirt before he made his way to Sans’s room.

Inside, it was hard to distinguish the clean clothes from the dirty ones. Sans’s dresser drawers were completely empty, all of the clothing in piles on the floor. Eventually, Papyrus found a stack of clothes that seemed cleaner than the others and picked out a shirt and a pair of shorts.

Sans was tucked under the covers when Papyrus returned, but he’d turned on the side-lamp that they always used for light when it was time for Papyrus’s bedtime story. Papyrus put the clothes on the pillow beside Sans and turned around to give him privacy. He was facing the bookshelf, so he focused on the spines of the books, trying to pick one that would be suitable for Sans.

There, a battered old human book that had fallen down with the trash. Sans had found it and brought it to Papyrus, saying that it reminded him of Papyrus because it had rabbits in it, just like Peek-A-Boo with Fluffy Bunny. Papyrus was smart enough to know what Sans was actually saying, and had kept it all of these years. He took it off the shelf now, and turned around to see Sans dressed in his clean clothes and sat upright in bed, halfway between sleepy and expectant.

“ALRIGHT, SCOOT IN CLOSE,” Papyrus said as he sat down, mirroring Sans’s routine and putting out an arm. Sans pressed close into Papyrus’s side, resting his skull on Papyrus’s shoulder-pad. “NOW, THIS BOOK IS CALLED ‘GUESS HOW MUCH I LOVE YOU.’ ARE YOU READY?”

“ready.” Sans put one of his hands on the cover of the book, tracing the deep scars left by its long fall from the human world above. Papyrus carefully opened the story to the first page, and began to read.

By the end of the book, Sans was snoring loudly. Papyrus read the last few pages as softly as he could and put the book on the bedside table. In the soft glow of the lamp, Sans looked peaceful. Papyrus hoped that he would sleep well here, and that he would still be in the mood for Papyrus to take care of him when he woke up.

In the meantime, Papyrus had spaghetti to prepare.

**Author's Note:**

> [ Here's an animated video ](https://www.youtube.com/watch?v=LPLwMxogYDU)of 'Guess How Much I Love You,' if you don't know the book already! 
> 
> Of course, neither Sans nor Papyrus has seen the moon, but I promise that when they get above-ground, they both think of this story every time they look up at it.


End file.
